Functional bis (perfluoroalkylsulfonyl) alkyl compounds

ABSTRACT

Bis(perfluoroalkanesulfonyl)substituted methanes possessing reactible groups such as halogen, hydroxyl, carboxyl or ester groups or possessing carbon-to-carbon unsaturation are provided. The residual hydrogen of the methane is relatively acidic and the compounds form metallic and organic salts which are recoverable. The molecule with acid hydrogen can be further reacted by the reactible group to incorporate an acidic hydrogen in another molecule such as a polymer. The acidic hydrogen effects absorption of basic vapors such as ammonia, amines, etc. Bis(perfluoroalkylsulfonyl) bromomethanes add to olefinic double bonds.

United States Patent Koshar [451 Sept. 11, 1973 Robert J. Koshar,Mahtomedi, Minn.

Inventor:

Assignee: Minnesota Mining and Manufacturing Company, St. Paul,

Minn.

Filed: May 1, 1972 Appl. No.: 249,244

Related US. Application Data Division of Ser. No. 807,408, March 14,l969, Pat. No. 3,704,31 l.

U.S. Cl 260/400, 260/481, 260/539 lint. Cl C07c 143/90 Field of Search260/400, 481, 539

References Cited UNITED STATES PATENTS 11/1972 Koshar 260/486 3,681,4l38/]972 Sweeney et al. 260/400 Primary ExaminerElbert L. RobertsAttorney-Alexander, Sell, Steldt & Delahunt [57] ABSTRACTBis(perfluoroalkanesulfonyl)substituted methanes possessing reactiblegroups such as halogen, hydroxyl, carboxyl or ester groups or possessingcarbon-to-carbon unsaturation are provided. The residual hydrogen of themethane is relatively acidic and the compounds form metallic and organicsalts which are recoverable. The molecule with acid hydrogen can befurther reacted by the reactible group to incorporate an acidic hydrogenin another molecule such as a polymer. The acidic hydrogen effectsabsorption of basic vapors such as ammonia, amines, etc.Bis(perfluoroalkylsulfonyl) bromomethanes add to olefinic double bonds.

1 Claim, No Drawings FUNCTIONAL BIS (PERFLUOROALKYLSULFONYL) ALKYLCOMPOUNDS This application is a division of copending application Ser.No. 807,408 filed Mar. 14, 1969, now U.S. Pat. No. 3,704,311. Thisinvention relates to bis(perfluoroalkanesulfo yl) methanes andparticularly to such sulfones additionally containing at least onereactible group such as hydroxyl, carboxyl, ester, bromine or chlorineor including carbon-to-carbon unsaturation.

Unsubstituted bis(perfluoromethanesulfonyl)methane is known from thework of Gramstad and Haszeldine, J. Chem. Soc. 4069(1957) and isdescribed by Brice and Trott in U.S. Patent No. 2,732,398. In addition,certain substituted monoperfluoromethanesulfonylmethanes were describedby Yagupolskii and coworkers in Russian publications. The variousunsubstituted bis(perfluoroalkylsulfonyl)'methanes are convenientlyprepared by reaction of the corresponding perfluoroalkanesulfonylfluoride with a methyl Grignard agent followed by metallation of themethyl perfluoroalkyl sulfone and reaction with more sulfonly halide.The terms perfluoroalkylsulfonyl" and perfluoroalkanesulfonyl are hereused as alternatives.

The novel compounds of the invention are members of the group consistingof: (RfSO2)2CMCH2CHBr (CH2) Y; (RfSO2)2CM(C H2n)OR and (R 50 CMW whereinM is H or ammonium, organic quarternary ammonium or 1-4-va1ent inorganicmetallic ions, R is perfluoroalkyl of one to about 18 carbon atoms, Y isH, Br, Cl, Or, COzR'; R is H, unsubstituted saturated acyl up to sevencarbon atoms or unsubstituted unsaturated acyl of three to four carbonatoms and R is H or unsubstituted alkyl up to eight carbon atoms, W isCL, Br, alkenyl of three to four carbon atoms or -4CH,CH(X)O-+,,H; Xbeing H or CH; and p= 1-10; (C,,H,,,) being divalent and having not morethan three carbon atoms separating valences, and n=l-6 and m=l-8.

It will be recognized that when M is H the compounds are the acids andthat the salts are compounds in which the acidic hydrogen has beenreplaced by an inorganic metallic cation or by an organic quaternaryammonium ion or was combined with a simple nitrogenous base to anammonium or monodior trisubstituted ammonium ion. Those skilled in theart will readily recognize that any amine having a degree of basicitywill form salts. Metallic cations may most easily be introduced by usesof carbonates, oxides, hydroxides or by disproportionation with salts ofvolatile organic acids.

From the one stand-point these novel compounds may be considered assubstituted bis(perfluoroalkylsulfonyl) methanes and salts thereof andfrom another as alkyl halides, alcohols, carboxylic acids and esterswhich provide protons with exceptional ease or the slats thereof. Thus,the acids absorb basic gases or vapors and polymers thereof may be usedto exchange for cations. The salts are often converted to acids byheating and undergo disproportionation reactions. Salts in which R isrelatively small tend to be water-soluble and.

as R, increases surface activity increases.

The acidic disulfones of the invention are generally high boilingnon-hygroscopic liquids, b.p. above 200 C., or solids having noappreciable or very low vapor pressure at or near room temperature. Theyform stable metal and organic salts which may precipitate metatheticallyor may be recovered by evaporation of a solution. These salts areparticularly useful for regeneration of the acidic sulfone by heat,e.g., they may be used as catalysts. In such conditions they exhibitsome latency. The acids are also liberated by treatment of the saltswith stronger acids, such as CF SO H, HCl or.

Metal salts are obtained with metals with valencies from l through 4,including alkali metal, e.g., potassium, sodium and alkaline-earth metalsalts e.g., calcium, strontium, as well as zirconium, iron, aluminum,copper, magnesium, nickel, zinc, lead and silver. Surprisingly suchsalts, including the silver salt are formed by the bromo and chlorodisulfones in which W is Br or Cl. The preferred salts are those withl-2-valent cations, ammonium and substituted ammonium.

Organic salts are obtained from organic nitrogeneous bases having a pKaof greater than about 1.5. Examples of amines which form salts with thedisulfones include pyridine, aniline, n-butylamine, 2-chloroaniline,cyclohexylamine, diethanolamine, diethylamine, methylamine,N-ethylaniline, piperidine, a-picoline, triethylamine, morpholine,guanidine, and aminoguanidine. More acidic disulfones also form saltsfrom less basic amines such as diphenylamine (pKa=0.85). Salts such asthe ammonium salt are prepared by reaction with ammonia. Quaternaryammonium hydroxides react to yield salts.

Certain. of the present compounds are prepared by formation of theorgano-metallic halide from unsubstituted.bis(perfluoroalkanesulfonyl)methane followed by reaction with a suitableorganic compound. The unsubstituted methanes known in the art bear twolike alkyl sulfonyl groups. Others bearing two unlike groups areprepared using different sulfonyl fluorides for preparing themethylsulfone and for reaction with the metal complex thereof in the aboveoutlined synthesis.

An organo metallic halide of the bis(perfluoroalkylsulfonyl)methane ismost conveniently prepared by reaction of the unsubstituted bis sulfonylmethane with a simple methyl Grignard reagent, e.g. CH MgCl or CH MgBrin a solvent such as anhydrous diethyl ether or tetrahydrofuran. Methaneis formed as a byproduct and a magnesio-organic derivative is obtained.Reactions are found to proceed in much the same way as conventionalGrignard reactions by reaction with halo: gen or alkyl or alkenylhalides or with an oxirane or with formaldehyde. Compounds prepared bythis method are intermediates for further reactions to form otherunsubstituted bis(perfluoroalkylsulfonyl)methanes by esterification ofOH or COJ-l groups, oxidation, reduction or by addition reactions makingnecessary allowances for the acidity of the compounds.

Another procedure for preparing certain compounds of the inventioninvolves an addition to a double bond of a bis(perfluoroalkylsulfonyl)bromomethane which may be formed by bromination as describedhereinbelow.

EXAMPLE 1 A dry, 250 ml. three-necked flask, fitted with stirrer,condenser and dropping funnel and gas measuring assembly is charged with2 5 g. (0.03 mole) of bis(perfluorooctylsulfonyl)methane, (C F,SO,),CH,, and ml. of tetrahydrofuran (distilled from LiAll-L). To thestirred mixture at room temperature is added 14 ml. of 3.0 molarmethylmagnesium chloride (0.04 mole) in tetrahydrofuran. A clearsolution results and 1,150 ml.

of gas (methane) is collected. After stirring at room temperature for 1hour, 5.1 g. (0.04 mole) of allyl bromide is added. The mixture isstirred at 60 C. for 1 hour further, cooled to C. and hydrolyzed by theslow addition of 25 ml. of 3N HCl followed by the addition of 250 ml. ofwater. The upper layer is decanted and lower layer diluted with 250 ml.of water. Filtration yields crude product which is first recrystallizedfrom chloroform and then slurried with 1,1,2-trichloro-1,2,2-trifluoroethane at room temperature and the mixture filtered.Evaporation of the filtrate yields 8.7 g. of4,4-bis(perfluorooctylsulfonyl)butene-1, (C F,,SO -CHCH CH=CH,,, m.p.8586.5 C.

The compound is characterized by elemental analysis as well as byinfrared and nuclear magnetic resonance (n.m.r.) spectroscopy Analysis:Calculated for C H F O S C, 23.7%; H, 0.6%; F, 63.3%: Found: C, 23.4%;H, 0.8%; F, 62.6%.

EXAMPLE 2 The procedure of Example 1, is repeated using a stirredsolution of 25 g. (0.09 mole) of bis(perfluoromethylsulfonyl) methane,(CF SO CH in 125 ml. of dry tetrahydrofuran at room temperature to whichis added 50 ml. of 3.0 molar methylmagnesium chloride (0.15 mole) intetrahydrofuran. Stirring is continued for one hour and then 18.2 g.(0.15 mole) of allyl bromide is added. After stirring at 60 C. for 1hour further and remaining at room temperature for hours, the mixture ishydrolyzed by the addition of 35 ml. of a saturated aqueous ammoniumchloride solution and 50 ml. of diethyl ether is added. The organicphase is separated and filtered and the solids washed with diethylether. Distillation of the filtrate gives 85 g.

of liquid residue. The residue is dissolved in water, acidified with 3Nhydrochloric acid and extracted with diethyl ether. Distillation of theextract (dried over MgSO gives 16.7 g. of4,4-bis(perfluoromethylsulfonyl)butene-1, (CF SO hCHCH CH=CH b.p. 101 C.(23 mm.).

The compound is identified by proton nuclear magnetic reasonancespectroscopy, infrared spectroscopy and elemental analysis. The infraredspectrum exhibits a weak C=C absorption at about 6.05 n.

Analysis: Calculated for C H F O S C, 22.5%; H, 1.9%; F, 35.6%; Found:C, 21.7%; H, 1.7%; F, 36.1%.

Other homologous haloalkenyl compounds, e.g., crotyl or isocrotylbromide, may be reacted in asimilar fashion as will be evident to thoseskilled in the art. The double bonds in the products may be oxidized toacids and also undergo other typical reactions of double bonds.

EXAMPLE 3 3,3-Bis(perfluorom'ethylsulfonyl)propan-Lo1 is prepared by thereaction of ethylene oxide (4.8 g.; 0.11- mole) with the magnesiumbromide complex (CF SO,) CHMgBr prepared in a dry 250 ml. flask, (fittedwith a stirrer, water condenser and dropping funnel) from 10 g. (0.036mole) of (CF SO ),CH in 100 ml. of anhydrous tetrahydrofuran and about16 ml. of a 3.29 molar solution of methylmagnesium bromide (0.05 mole)in diethyl ether. The reaction mixture is stirred at room temperaturefor 1.5 hours and hydrolyzed with 100 ml. of 3N l-lCl. Extraction withdiethyl ether followed by distillation of the extract (dried over MgSOyields 1.6 g. of(CF SO CHCH C1-l ()1-1, b.p.

112 C. (4.5 mm.). The compound is characterized by its infrared andproton n.m.r. spectra. The n.m.r. spectrum exhibited absorptions ('r) at4.50 (CH; triplet), 6.08 (-CH CH OH; triplet), 7.30 (CH CH OH;quadruplet) and 7.60 (OH).

When formaldehyde vapors are employed in place of ethylene oxide theproduct is 2,2-bis(perfluoromethylsulfonyl)ethanol. When trimethyleneoxide (oxetane) is used the product is 4,4-bis(perfluoromethylsulfonyl)butanol-1. Other epoxy compounds which are usedinclude propylene and isobutylene oxide, epichlorhydrin and2,3-epoxypentane.

EXAMPLE 4 Using the above procedure of Example 3, 3,3-bis(perfluorobutylsulfonyl )propan- 1 -o 1 is prepared from 21.5 g.(0.04 mole) of bis(perfluorobutylsulfonyl)methane, (C F SO CH in 125 ml.of anhydrous tetrahydrofuran.

Recrystallization of crude product from carbon tetrachloride gives (CF,,SO CHCH CH OH, m.p. 58-60 C.

Analysis: Calculated for c mr o s C, 21.2%; H, 1.0%; F, 54.8%; Found: C,21.0%; H, 1.0; F, 55.0%.

EXAMPLE 5 Using the procedure of Example 2,bis(perfluorometylsulfonyl)bromomethane is prepared by adding bromine(24 g.; 0.15 mole) to a stirred tetrahydrofuran solution at roomtemperature of (CF SO CHMgCl (from 25 g. (0.09 mole) ofbis(perfluoromethylsulfonyl)methane and methylmagnesium chloride as inExample 2). The mixture is stirred at room temperature for 1.5 hours andat 60 C. for 1 hours, hydrolyzed with ml. of 3N HCl and thetetrahydrofuran phase separated and the tetrahydrofuran evaporated underreduced pressure. The residue is washed with water and dissolved indiethyl ether. Distillation of the ethereal solution (dried over MgSOgives 26.5 g. of (CF SO ),CHBr, b.p. 93-95 (9 mm.). The proton n.m.r.spectrum exhibits a strong singlet at 3.751- characterizing the singlehydrogen atom.

EXAMPLE 6 This example illustrates the preparation of the unsymmetricalsulfone, C F SO CH SO CF To a dry stirred solution of 16 g. (0.11 mole)of methyl perfluoromethyl sulfone and 75 ml. of dry tetrahydrofuran atabout 10 C. and under nitrogen is gradually added 40 ml. of 3.0 molarsolution of methylmagnesium chloride in tetrahydrofuran (methaneevolved). The mixture is allowed to warm to room temperature and 55.2 g.of perfluorooctanesulfonyl fluoride is added. The mixture is stirred atroom temperature for 2 hours and then under reflux for 1 hour. Afterhydrolysis of the mixture with 75 ml. of 3N hydrochloric acid, threephases result. The upper organic phase is separated and evaporated underreduced pressure to yield 28 g. of solid residue-The solid is slurriedwith 10 percent aqueous sodium bicarbonate solution, the aqueous phaseacidified and then extracted with diethyl ether. Evaporation of theethereal solution yields 22 g. of C F SO CH SO CF which isrecrystallized from carbon tetrachloride, m.p. 106108 C.

Analysis: Calculated for C H F O S C, 19.2%; H, 0.3%; F, 60.3%; Found:C, 18.8%; H, 0.3%; F, 59.9%.

By reactionwith an excess of ethylene oxide and propylene oxide usingthe general procedure of Example 3 (and of Example 14 below) substitutedalcohols are prepared having structures (C,F SO )(CF,SO,Cl-lcn cn o Hand where n is from 1 to about 8.

EXAMPLE 7 Bis(perfluoromethylsulfonyl)bromomethane is prepared bybromination of the mono-potassium salt ofbis(perfluoromethylsulfonyl)methane. A solution of 48.2 g. (0.17 mole)of bis(perfluoromethylsulfonyl)methane and 225 ml. of anhydrous methanolis neutralized with 13.1 g. (0.09 mole) of potassium carbonate. Themixture is filtered and the filtrate evaporated to dryness. The sale isdried, suspended in 225 ml. of carbon tetrachloride and 27.6 g. (0.173mole) of bromine in 30 ml. of carbon tetrachloride is added. The mixtureis stirred at room temperature for 1 hour and under reflux for 1.5hours. The mixture is filtered and the filterate distilled to yield 56.5g. of (CF SO CHBr, b.p. 9394.5 C. (9 mm.).

Analysis: Calculated for C l-lBrF,O,S,: C, 10.0%; Br, 22.3%; F, 31.7%;Found: C, 9.9%; Br, 22.4%; F, 31.5%.

EXAMPLE 8 To a suspension of 25 g. (0.08 mole) of the potassium salt ofbis(perfluoromethylsulfonyl)methane prepared as described in Example 7is added 5.5 g. (0.08 mole) of chlorine. The mixture is stirred at roomtemperature for about 2 hours and then filtered. Distillation of thefiltrate yields, bis(perfluoromethylsulfonyl)chloromethane (CFSO,),C1-lCl, b.p. 8486 C. (18 mm.).

Analysis: Calculated for C:l-1C1F,0,S,: C, 11.5%; CI, 11.3%; H, 0.3%;Found: C, 11.2%; C1, 13.2%; H, 0.2%.

EXAMPLE 9 Using the procedure described in Example 7, bromination of thepotassium salt of bis(perfluorobutylsulfonyl)methane yieldsbis(perfluorobutylsulfonyl) bromomethane (C F,SO,),CHBr which ispurified by recrystallization from heptane, m.p. 61.5-62.5 C.

Analysis: Calculated for C.1-1BrF O S,: C, 16.4% F, 52.0%; Br, 12.1%;Found: 16.5%; F, 52.3%; Br, 11.3%.

Other disulfones which are prepared by procedures described in Examples7-9 include C,F,-,SO,Cl-1C- lSO CF (C,F,-,SO,),CHC1, (C F,-,S0,),CHBr, CF,,SO,C1-lBrSO,CF and C F, S0,C1-lBrSO,C,F,. Compounds of the type(R,SO,),C1-1Br add to terminal duble bonds as shown in the followingexamples.

Other compounds of the invention are made by addition ofbis(perfluoroalkylsulfonyl)bromomethanes (prepared as above) toa,B-unsaturated compounds Y(CH ),,,CH=CH, which may be aliphatichydrocarbon or may contain other substituted groups such as carboxyl,carboalkoxy, acyloxy, etc. This leads to the series of compounds whichinclude a fi-halogen atom.

Further compounds of the invention are formed from EXAMPLE 10 A quartzflask, equipped with a condenser and magnetic stirring bar, is chargedwith 10 g. (0.04 mole) of bis(perfluoromethylsulfonyl)bromomethane, 6ml. of methylene chloride and 3.6 g. (0.04 mole) of 4- chlorobutene-l.The mixture is stirred for 4 hours at ambient temperature under theillumination of a watt l-lanovia ultraviolet lamp, allowed to remain atroom temperature for 15 hours and is then distilled to yield 6.3 g. ofthe adduct, 1,1- bis(perfluoromethanesulfonyl)-3-bromo-5- chloropentane(CF SO CHCl-l,CHBrCH,Cl-1 Cl, b.p. 9394 C., at 0.05 mm. Hg.

Analysis: Calculated for C-,l-l,;F,BrClO,S,: C, 18.7%; F, 25.3%; H,1.8%; Found: C, 18.7%; F, 25.4%; H, 1.9%.

EXAMPLE ll A quartz bulb is charged under nitrogen with 10 g. (0.04mole) of bis(perfluoromethylsulfonyl)bromomethane and 3.5 g. (0.03 mole)of freshly distilled octene- 1 (exothermic reaction). The bulb is closedand stirred at room temperature for 15 hours under ordinary light.Distillation yields the adduct, (CH;,SO,),CHCH,Cl-1Br- (Cl-19 C11 b.p.97-97.5 C. at 0.1 mm. Hg.

Analysis: Calculated for C H E,BrO,S,: C, 28.0%; F, 24.2%; Br, 17.0%;Found: C, 28.9%; F, 24.2%; Br, 16.2%.

EXAMPLE 12 Using the procedure of Example :10, a mixture of 10 g. (0.04mole) of bis(perfluoromethylsulfonyl)- bromomethane, 6 ml. of methylenechloride and 3.5 g. (0.04 mole) of 3-butenoic acid is illuminated for 6hours. A white solid precipitates. Filtration gives 6.0 g. of theadduct, (CFhd 3SO,),CHCH,CHBrCH,CO,l-l, which is recrystallized fromchloroform, m.p. 147-l48 C.

Analysis: Calculated for C,l-l-,BrF,0,S,: C, 18.9%; F, 25.6%; H, 1.6%;Found: C, 19.1%; F, 25.7%; H, 1.8%.

The acid is converted to esters by reaction with alcohols in thepresence of a suitable acidic catalyst.

Adducts of (CF,SO,),Cl-1Br are prepared by analogous reactions withother terminally unsaturated oleflns such as propene, butene-1,pentene-l, undecylenic acid and its esters, undecenyl bromide, undecenylalcohol (CH,=CH(CH,),OH and esters thereof), and like compounds.

The higher bis(perfluoroalkylsulfonyl)bromomethanes in which alkyl isethyl, octyl, etc. are also used as addends with the above describedolefins and yield compounds of the invention.

EXAMPLE 13 A 50 ml. flask equipped with a magnetic stirring bar,condenser and Barrett wate receiver is charged with 6.2 g. of.3,3-bis(perfluorobutylsulfonyl)propan-l-ol from Example 4, 15 ml.ofbenzene and 0.002 g. of phenothiazine. The mixture is heated todissolve the disulfone and 1.0 g. (0.014 mole) ofacylic acid is addedfollowed by 0.06 g. of concentrated sulfuric acid. The mixture isstirred under reflux for 20 hours and water continuously removed. Themixture is evaporated under reduced pressure and the'residue dissolvedin hot heptane. Cooling of the heptanesolution to about 0 C. gives 2.6g. of insoluble, moderately viscous liquid 3 7' which is mainly3,3-bis(perfluorobutylsulfonyl)propyl acrylate fonyl)propyl acrylate].Elastomeric films of the polymer are cast from benzotrifuloridesolution. This appears to contain from 2 and more up to a few hundrede.g. 300 monomer units.

Using the above procedures the methacrylate monomer,

and its homo polymer are prepared.

EXAMPLE 14 Propylene oxide (1.7 g.; 0.03 mole) in 10 ml. of drytetrahydrofuran is slowly added to a stirred mixture of 7.0 g. (0.03mole) of bis(perfluoromethylsulfonyl)methane and 20ml. oftetrahydrofuran. The reaction is immediately exothermix and the additionis controlled so that the temperature does not exceed 30 C. The mixtureis refluxed for 1 hour and distilled to yield 5.9 g. of unreacteddisulfone and 2.1 g. of a viscous liquid which does not distill at 160C. (0.1 mm.). The residue containing (CH SO )-,CH[CHCH(CH,)O],,-H has afluorine content of about 12.5 percent and an average molecular weightof 666. The value of n in the formula is about 7.

A similar compound is made usingethylene oxide.

EXAMPLE The disulfones of the invention are useful as catalysts forpolymerization of cationic-sensitive monomers, e.g., epoxides.

Bis(perfluoromethylsulfonyl)chloromethane (Example '8) (0.05 g.) isdissolved in methylene chloride and added with stirring to 3.0 g. of3,4-epoxycyclohexylmethyl-3,4-epoxy-cyclohexane carboxylate (UnionCarbide ERL-422l epoxy monomer) at room temperature. After about 0.1minute a hard brittle polymer is obtained. Similarly, (C F SO ),CHCHCH=Cl-l is used with the above epoxy monomer and after mixing 'at 1 15C. for 3 minutes a hard brittle'polymer is obtained. The propertires ofthe polymer depend upon the monomer rather than on the particularcatalyst used. Other monomers are polymerized by similar proceduresusing compounds of y the invention. p

The following examples show the use of the disulfones of th invention asagents for removal of gaseous basic contaminants, such as ammonia oramines, from gas mixtures. In addition to solid supports which aredescribed, inert solvents such as methylene chloride, carbontetrachloride, glyme, chloroform and tetrahydrofuran are used insuitable bubbling tubes.

The non-polymeric disulfones, expecially when R, is CF exhibit highsolubility in inert solvents such as those immediately above and thesolutions are useful in analytical work for the titration ofmoisture-sensitive bases.

EXAMPLE 16 To a stirred mixture of ml. of methylene chloride and 11 g.of calcined diatomaceous earth aggregate (chromasorb P,'30/40 mesh),which is essentially nonreactive toward amines and is used as an inertsupport, is added 3.0 g. (about 0.0095 mole) of the disulfone, (CFSO,),CHCl. Evaporation of the solvenet under reduced pressure yields afree flowing solid containing about 22 percent by weight of thedisulfone.

A dry U shaped tube is packed with ll g. of the above solid and about0.01 mole of anhydrous dimethylamine, diluted with nitrogen, is allowedto pass through the solid at ambient temperature. The tube becomes warmduring the process indicating reaction and absorption of the amine. Theabsorbent is essentially fully saturated with amine.

EXAMPLE 17 EXAMPLE is y The following examples illustrate the formationof salts of the disulfones of the invention.

A solution of2 g. (0.006 mole) of (CF SO ),CHBr in absolute metanol isneutralized with 0.3 g. of anhydrous sodium carbonate. The mixture isfiltered and the filtrate evaporated to dryness. The solid product isslurried with carbon tetrachloride to remove any unreacted disulfone,azeotropically dried with benzene under reduced pressure and the residuedired in vacuo at 90 C. There is obtained 1.5 g. of (CF SO,){CBr*Na,m.p. (dec.) 254-256 C.

Analysis: Calculated for C BrF,0 S,Na: C, 9.5%; Br, 21.0%; F, 29.9%; Na,6.0%; Found: C, 9.7%; Br, 20.9%; F, 29.8%; Na, 5.8%.

EXAMPLE 19 Using procedures similar to those described above, thepotassium, zinc, calcium, silver and cupric salts of (CF SO,) CHBr areprepared by neutralization with the corresponding carbonate, oxide orhydroxide. The appearances and melting points (usually withdecomposition) of the salts are as follows: potassium (white; m.p., dec.is 240-24S C.), zinc (white; m.p., dec. above 250 C.). calcium (white;m.p., dec. above 250 C.), silver (white, soluble in methanol and lightsensitive; m.p. dec. C.), cupric (green; m.p. dec., above 250 C.). Thefact that the silver salt does not readily deposit silver bromidespontaneously is noteworthy. Alkoxides, e.g. NaOMe, Al(i PrO),, etc. arealso used to form salts with acidic disulfones.

EXAMPLE 20 To a stirred solution of 5.0 g. (0.014 mole) of (CF SO CHBrand 25 ml. of benzene is added 2.0 g. (0.19 mole) of triethylamine. Themixture is stirred at 6070 for four hours; two liquid phases result. Thelower phase is separated and slurried with dry diethyl ether to yield5.3 g. of insoluble oil which is mainly the salt. (CF SO CBrHN (C H Thesalt is soluble in hot water and chloroform.

EXAMPLE 21 A solution of 1.0 g. of (CF SO CHCl in ml. of diethyl etheris neutralized with about 0.5 g. of 2- chloroaniline (pKa=2.65). Thesolution is evaporated and the residue slurried with cold carbontetrachloride yielding 0.6 g. of insoluble salt. m.p. l20l23 C.

Under similar conditions the 2-chloroaniline salt of (CF SO CHCl-lCl-l=Cl-l is prepared. This salt, m.p. 5760 C., is very soluble indiethyl ether, and partially soluble in carbon tetrachloride. Salts withother oganic bases and quarternary ammonium hydroxides are prepared insimilar ways.

The above salts as well as other organic salts of the describeddisulfones are identified readily by infrared spectroscopy because thesalts usually exhibit SO absorption at about 7.5 microns compared to thestarting acidic disulfones which generally exhibit absorption for S0 at7.2-7.25 microns. Other prominant absorptions for the salts occurbetween 9.5-l0.5 microns.

The surfactant properties of certain of the above salts are particularlyevident for perfluoroalkyl groups of four or more carbons. A 0.l percentsolution of (CF SO CBrK has a surface tension at 25 of 73 dynes/cm. ascompared to distilled water which is 76 dynes/cm. At the sametemperature, 0.0] solutions of (C.,F SO CBrK and (C F SO 'CCH CH=Cl-l Nahave values of 49 and 26 dynes/cm. respectively.

What is claimed is:

l. A compound selected from the group of substitutedbis(perfluoroalkylsulfonyl)methanes consisting of (R,SO CMCH CHBr(CH),,,CO R wherein:

M is H or cations of ammonium, organic quaternary ammonium or 1-4-valentinorganic metallic ions;

R, is perfluoroalkyl of one to about 18 carbon atoms,

R is H or unsubstituted alkyl up to eight carbon atoms and m is l to 8.

\ UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent 5.758.531Dated September 1 1 I075 Inventor(s) Robert J. Koshar It is certifiedthat error appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

Column 1, line 56 "CL" should read --Cl-- Column 1, line 58 "slats"should read salts--:

Column line 55 "hours" 2nd occurrence should read --hour-- Column 5,line 5 the formula (CH CH O)H should read CH CH O H--. 7 Column 5, l ine 55 "duble" should read --double-- Column 6, )line 57 the formula(CFhd 580 should read cr so 1 C Column 6, line 57 "wate" should read--water-- Column 6, line 61 "acylic" should read -acrylic-- Column 7,line 50 "exothermix": should read v--exothermic-- Column7, line 5%propercires" should read --properties-- Column 7, line 60 "th" shouldread --the-'-- r 7 Column 8', line 11 "solv'enet" should read solvent-Signed and sealed this 22nd day of January 19714..

(SEAL) Attest:

EDWARD M.'FLETCI-IEIR, JR. I RENE D. TEGTME-YER Attesting Officer IActing Commissioner of Patents

